Every day for two hellish years the Japanese brutes tried to break the young American POW.

They could have killed Louis Zamperini at any moment but that would have spoilt the sadistic satisfaction of two camp guards known as The Butcher and The Bird.

So they tortured him to the brink of death – then pulled him back for more agony.

He was fed scraps of meat writhing with maggots and rubbed in rat droppings, he was injected with Dengue fever, beaten round the temples with a metal buckle and forced to lick his captors boots.

Once he was ordered to stand holding a log above his head as he was punched repeatedly in the stomach.

After 37 minutes furious guards gave up waiting for him to collapse and beat him to the ground.

They had picked on the wrong prisoner. The former Olympic runner had already survived a plane crash, 47 days at sea without food or water, shark attacks, then capture and interrogation.

Before the war, at the Berlin Games, Zamperini had been forced to shake Adolf Hitler’s hand and listen to the Nazi ­dictator’s small talk. So once the dignitaries had gone, he shinned up the flagpole and stole the Fuhrer’s personal standard.

That was the fiery determination that ensured Louis Zamperini could never be broken. And 70 years on it has inspired Hollywood star Angelina Jolie to make a film of his life story.

Louis Zamperini died last week at the age of 97, just months before the release of her movie Unbroken.

But his incredible tale of heroism will live on when it hits screens around the world this summer.

Angelina, who had grown incredibly close to him, called him “her hero” and led the tributes after he succumbed to pneumonia.

She said: “It is a loss ­impossible to describe. We are all so grateful for how enriched our lives are for having known him. We will miss him terribly.”

Louis was born in January 1917 to Italian immigrants in Olean, New York State, before his family moved to California.

Growing up in relative poverty he showed a talent for sport and at first took up boxing to defend himself from bullies before switching to athletics.

“I had made up my mind to run ­everywhere,” he said. “Instead of hitchhiking to the beach four miles, I ran to the beach.

"All summer long, that’s what I did. But I had no idea how fast I could run.”

After winning his first race he said: “I looked back and I had won it by a quarter of a mile. I thought I must have cut some corners but they assured me that I ran the full course.

"I had no idea I was in such good shape because I had never timed myself. I just ran, ran, ran. So then I realised that I could really be a runner.”

By the age of 17, at school in the Los Angeles suburb of Torrance, he broke all local records to earn the nickname the “Torrance Tornado”.

And in 1936 he was part of the USA team at the Berlin Olympics, running in the 5,000 metres, not his best distance, in front of Adolf Hitler.

Although he came eighth he created headlines around the world after running the last lap in only 56 seconds. His efforts clearly left a mark on Hitler, who told him: “Ah, you’re the boy with the fast finish.”

Louis had hoped to do better in the 1940 Olympics, but they never happened. The Second World War broke out and at 27 he was drafted in to the US Army Air Corps as a bombardier and posted to the South Pacific.

On a reconnaissance mission in 1943, his B-24 Liberator plane crashed in to the sea, killing eight crew.

With two other survivors he scrambled into a life raft and they braved prowling sharks, drank rain water and ate fish and birds caught with their bare hands to stay alive.

One man died of starvation but Louis and the pilot survived on the open sea for 47 days, drifting for 2,000 miles and losing half of their normal body weight.

His parents were told he had been killed in action but in fact the pair were spotted by the Japanese Navy and taken prisoner.

It was the start of two years of physical and psychological torture in a succession of POW camps.

One was known as Execution Island because few Allied captives ever lived to tell of their time there.

Louis said: “When I took off my blindfold my brain and my eyes fluttered with the unreality of it all.

“After nearly two months floating under open skies and infinite seas, I found myself locked in a cubicle the size of a dog kennel.

“The instant claustrophobia made me want to scream, but I was too weak. Instead, I lay down and looked at my body.

“Just six weeks before I’d been a vigorous athlete who could run a mile in just over four minutes. Now I was fleshless, skeletal.

“All my life I had kept my emotions tightly in check when it came to my own troubles, but I could no longer help myself. I broke down and cried.”

But he never let his captors break him, though he was moved to a secret ­interrogation camp on the Japanese ­mainland, where the smallest violation of rules resulted in severe beatings.

These were often at the hands of the medical officer, a pitiless brute called Sueharu Kitamura, known as “the Butcher”.

Starvation rations were infested with maggots, rat droppings and sand and grit that split and cracked the captives’ teeth.

In September 1944 he was transferred to Omori, a man-made sand-spit between Yokohama and Tokyo. Conditions were atrocious and prisoners died of abuse, neglect and malnutrition.

One guard, Corporal Mutsuhiro Watanabe, was known as “The Bird” and he became obsessed with humiliating the famous Olympian.

Some men were summarily executed but bullying Watanabe insisted that Louis was kept on the edge of death but never allowed to die. He beat him every day and ordered his fellow PoWs to do the same.

Once, on Watanabe’s orders, Louis was punched in the face by each of his 220 fellow-inmates, who faced death or brutal punishment if they refused.

Watanabe himself would often beat Louis on the temple with the heavy brass buckle of his belt, then help him staunch the blood and whisper words of comfort before attacking him again in exactly the same way.

As the tide of war turned against Japan, “The Bird” grew even more violent towards Louis, who became convinced he would be killed before liberation.

“I could take the beatings and physical punishment,” he said later. “But it was the attempt to destroy your dignity, to make you a nonentity... that was the hardest thing to bear.”

In September 1945 Allied forces reached the camp and Zamperini was freed to go home to a hero’s welcome.

But he was a changed man. Though he met and married his wife Cynthia in 1946 he battled anger, depression and alcoholism and at one point became obsessed by the thought of returning to Japan and killing Watanabe, his chief persecutor.

The mental torment almost cost him his marriage, but in the end he got his life back on track after finding God. He worked as an inspirational speaker and preached about the power of forgiveness. He and Cynthia, together until she died in 2001, had two children, Cissy and Luke.

Finally, at the age of 81, he did return to Japan to run a leg of the torch relay at the Nagano Olympics. He ran past the former camps where he had been imprisoned.

By then Watanabe – who had been condemned as a war criminal but evaded prosecution – had been discovered. He was a successful businessman who had made a fortune from insurance.

Louis wrote to him offering to meet, saying: “The one who forgives never brings up the past to that person’s face.

"When you forgive, it’s like it never happened. True forgiveness is complete and total.”

Watanabe refused to meet but gave an interview to the American TV show 60 Minutes, claiming he had treated his victim “only as an enemy of Japan”.

Louis wrote two memoirs but it was a bestselling biography published in 2010 that won the attention of ­Angelina.

Unbroken: A World War II Story of Survival, Resilience, and Redemption by Laura Hildebrand provoked huge interest in Louis at a time when he had lost most of his pals and felt very alone.

“It’s sad to realise that you’ve lost all your friends,” he said. “ But I think I made up for it.

"I made a new friend – Angelina Jolie. And the gal really loves me. She hugs me and kisses me, so I can’t complain.”

He was her guest last year when she was presented with the Jean Hersholt ­Humanitarian Award by the Academy of Motion Picture Arts and Sciences.

Asked to sum up his life during the ceremony, Louis simply replied: “God has given me so much. He expected so much out of me.”